A U-band survey of brown dwarfs in the Taurus Molecular Cloud with the XMM-Newton Optical/UV Monitor

Simple item page
dc.creatorGrosso, Nicolas
dc.creatorAudard, Marc
dc.creatorBouvier, Jérôme
dc.creatorBriggs, Kevin R.
dc.creatorGüdel, Manuel
dc.creatorCloud, the The XMM-Newton Extended Surveyof the Taurus Molecular
dc.creatorCollaboration
dc.date2006-09-01
dc.date.accessioned2026-07-07T11:42:35Z
dc.date.available2026-07-07T11:42:35Z
dc.descriptionWe aim to characterize the U-band variability of young brown dwarfs in the Taurus Molecular Cloud and discuss its origin. We used the XMM-Newton Extended Survey of the Taurus Molecular Cloud, where a sample of 11 young bona fide brown dwarfs (spectral type later than M6) were observed simultaneously in X-rays with XMM-Newton and in the U-band with the XMM-Newton Optical/UV Monitor (OM). We obtained upper limits to the U-band emission of 10 brown dwarfs (U>19.6-20.6 mag), whereas 2MASSJ04141188+2811535 was detected in the U-band. Remarkably, the magnitude of this brown dwarf increased regularly from U~19.5 mag at the beginning of the observation, peaked 6h later at U~18.4 mag, and then decreased to U~18.65 mag in the next 2h. The first OM U-band measurement is consistent with the quiescent level observed about one year later thanks to ground follow-up observations. This brown dwarf was not detected in X-rays by XMM-Newton during the OM observation. We discuss the possible sources of U-band variability for this young brown dwarf, namely a magnetic flare, non-steady accretion onto the substellar surface, and rotational modulation of a hot spot. We conclude that this event is related to accretion from a circumsubstellar disk, where the mass accretion rate was about a factor of 3 higher than during the quiescent level.
dc.description6 pages and 4 Figures. Accepted by A&A, to appear in a special section/issue dedicated to the XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST)
dc.identifierhttps://arxiv.org/abs/astro-ph/0609027
dc.identifierhttp://arxiv.org/abs/astro-ph/0609027
dc.identifierAstron.Astrophys.468:557-562,2007
dc.identifierdoi:10.1051/0004-6361:20065425
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/200937
dc.subjectAstrophysics
dc.titleA U-band survey of brown dwarfs in the Taurus Molecular Cloud with the XMM-Newton Optical/UV Monitor
dc.typetext

Files

Collections

arXiv